A miniature peristaltic pump is described in Diabetic Care, Volume 3, No. 2 of March-April, 1980. This publication was prior to the application for process U.S. Pat. No. 4,452,599 of Albissor et alia. The work of Albissor concentrated on the concept of a double tube system. The chamber of such a pump holds the tubing and the rotor and is contained inside a cover which constitutes the stator. The eccentric rotor squeezes the resilient tubing which is in a single loop inside the circular stator, and thereby pushes the liquid in the tubing from an inlet port to an outlet port. The major use for peristaltic pumps is Biomedical. Ideally, a pump chamber should be assembled and ready for insertion by connecting the external inlet and outlet ports to tubing running from the source of medication to the sink for medication. However, the structure of the stator and the eccentricity of the rotor results in a pinched resilient tube inside the chamber. Not only can this pinch result in a permanent occlusion, but it prevents gravity flushing of air bubbles from the system. If one removes a chord from the arc of the stator, it will leave the resilient tubing free from becoming pinched at a set position of the rotor, so the tubing remains an open channel. By inserting the arc, the stator is complete and the liquid may be pumped.
The major portion of the structure of a peristaltic pump is in the rotational drive means or motor. This application describes an improvement on the small peristaltic pumps used in medical applications by the introduction of a head system separate from the motor which can be preloaded with tubing and stored for future and rapid use. It also permits the tubing to be loaded with medicament by gravity flow while inserted in the head because of the unoccluded passage if the cap is not attached.